You probably don’t have your laptop configured to send email, but for the reasons you outline I put something like this in all of the importers that I touch:
SiteSetting.disable_emails = true
SiteSetting.allow_index_in_robots_txt=nil
SiteSetting.login_required=true
Oh. Yeah. Email’s not stored in the user table anymore. If you go to /admin/users you can see them.
If you don’t include a name, it uses their username.
See this post for a code sample that pulls email addresses.